Our regular DXTV columnists Keith Hamer and Garry Smith offer a series of special articles on the history and technology of TV in the UK, beginning with a two-part analysis of recent changes to the BBC Weather Forecast.

 

The BBC Weather Forecasts have been provided by the Meteorological Office almost from the time of the birth of the world’s first radio service. The weather service is often abbreviated to the ‘Met Office’, which eases the tongue-twister for some radio and television announcers!

The Met Office has always been part of the MoD (Ministry of Defence) and is called upon to provide forecasts to the government, especially in times of war and conflicts around the world.

The BBC (originally known as the British Broadcasting Company Limited) was officially formed on October 18th, 1922. The first programme was broadcast on November 14th from the 2LO London Station.

The first daily weather forecast was broadcast on April 29th, 1923.

The BBC Television Service began on November 2nd, 1936, and the world’s first television weather forecast was transmitted the following day at 4.01pm (Fig. 1). It lasted approximately six minutes and consisted only of a weather chart, with an anonymous hand drawing in the isobars (lines of equal air pressure) on it.

Rather strangely, the forecast was accompanied by a little light music in the background.

 

In-Vision Weather and Magnetic Rubber

The first in-vision ‘weatherman’ on British television was George Cowling. He presented his first forecast from the BBC studios at Lime Grove on January 11th, 1954 (Fig. 2). George had joined the Met Office in 1939 as a meteorological assistant for the RAF. He continued his career to work as a forecaster in France, Belgium, Germany and The Netherlands.

He appeared on the BBC until 1957 and remained with the Met Office until his retirement in 1981. He died on Christmas Eve, 2009. In-vision weathermen had also appeared in Belgium, Germany and the Netherlands.

By 1963, there were two regular weather forecasters, at a time when there was only the single BBC channel.

Bert Foord and Graham Parker took it in turns to provide viewers with the latest weather updates (Fig. 3).

The black isobars were originally drawn on a map using a marker pen until a huge metallic Atlantic Chart was introduced. Isobars were subsequently painstakingly produced using strips of magnetic rubber.

If there was a deep low-pressure system, the results could almost resemble a work of art. Following each ‘live’ forecast, the magnetic rubber was taken down, ready for use in the next, updated, forecast.

In total, the Met Office has supplied the BBC with weather forecasts for the past 95 years.

However, In August 2015, the BBC announced that it was changing its weather forecasting provider to, quote, "secure the best value for money for licence-fee payers". How the savings of, quote, “millions of pounds,” will actually be achieved still hasn’t yet been explained by the BBC.

After all, the new provider will have to collect accurate weather data from somewhere, and this comes, naturally, at a cost.

 

Unrivalled Weather Data Technology

Somewhat bizarrely, most of the data used by the new provider will be sold to them by the Met Office! As a part of the MoD, the Met Office has an unrivalled network of data sources, including their 200 UK weather stations and 15 weather radars (which measure wind velocity) as well as up-to-the-minute feedback from commercial ships and from aircraft, which capture meteorological data from the crafts’ onboard navigation systems.

Meteorological data is collected by commercial aircraft using a software programme called AMDAR (Aircraft Meteorological Data Relay), which was initiated by the World Meteorological Organization (WMO).

www.wmo.int

The system employs standard temperature and static pressure probes. The data is processed before transmitting the information back to Earth, either via VHF communication or through a satellite link.

Weather information transmitted on VHF frequencies relies on the ACARS (Aircraft Communications Addressing and Reporting System) digital data system, whereas signals using a satellite link utilise ASDAR (Aircraft-to-Satellite Data Relay).

ASDAR technology consists of an 80Watt transmitter on 402MHz with a flat antenna. A microprocessor unit is used for coding data, which has been collected by the aircraft’s flight data acquisition equipment.

The RAF also operates aircraft fitted with specialised sensitive meteorological equipment.

In addition to this, the Met Office uses a method of collecting atmospheric data known as a ‘radiosonde’.

This technique employs a helium-filled balloon to transport an array of sensors up through the atmosphere, at 5m per second, and to a height of around 25 km.

As it ascends, temperature and relative humidity measurements are recorded at two-second intervals. A GPS receiver allows the radiosonde location to be identified. Various collected data such as pressure, wind speed and direction can subsequently be calculated and transmitted back to Earth.

Radiosondes usually operate on 403MHz or 1.680 GHz. They are launched around the world at the official observation times of 00:00 and 12:00 UTC (GMT).

All these sources of data combine to supply 106m weather observations every day. These are fed into the Met Office’s expensive, extremely high-tech, computers. These then ‘crunch the numbers’ and print out the raw weather charts. The charts are ultimately transformed, by unseen experts, into the familiar on-screen graphics at the Met Office and, subsequently, explained by the well-known (and the not so well-known) weather presenters (Fig. 4).

 

Weather Important for DXers

The atmospheric conditions at any given time hold a special interest for DX enthusiasts. During periods of intense anti-cyclonic (high-pressure) weather, FM and television signals from distant transmitters within the UK or Europe may be received via enhanced tropospheric conditions.

Moreover, under conditions of exceptional enhancement, transmissions from further afield may also be encountered. It is always a good idea to watch the daily weather forecasts to gain advance information about any approaching high-pressure systems.

There is a lot of very useful information provided by the Met Office, which DXers should find interesting. Their main website is at this URL:

www.metoffice.gov.uk

Furthermore, there are several other internet sites, which are devoted to assisting DXers. Many enthusiasts rely on resources such as DX Maps, which can be found here:

www.dxmaps.com

This online tool displays paths for different modes of propagation and also the frequencies affected.

The William Hepburn colour contour maps are also very useful and are to be found at this website:

www.dxinfocentre.com

Todd Emslie (Australia) makes frequent use of this site for predicting long-haul tropospheric paths between New Zealand and Australia.

And Nick Gilly (Whitchurch, Hampshire) consults the following website:

www.tropo.f5len.org

The site features coloured areas depicting the strength of an opening. The displays can easily be ‘clocked forward’ through three-hour intervals.

Finally, another very useful website is at this URL, even if you have little German:

www.wettermonitor.de

   The site links in with the (German) weather monitoring software Zorns Lemma.

Yahoo and some of the DX group ‘chat’ sites offer weather alerts, either via E-mail or SMS.

However, this does not guarantee that reception will intrude into your particular location. Alerts do have their advantages if you have limited leisure time to devote to the hobby and are therefore unable to spend time checking prevailing conditions yourself. Someone else has done the donkey-work for you.

There is a range of valuable help available to the DXer, compared with what there was decades ago.

In next month’s instalment, we will be looking at satellite technology, severe weather warnings, ‘tendered weather’ and other areas. See you then.

Editor’s Reading Tips

 

Denny, M. (2017) Making Sense of Weather and Climate: The Science Behind the Forecasts

Halford, P. (2004) Storm Warning: The Origins of the Weather Forecast

Henson R. (2010) Weather on the Air: A History of Broadcast Meteorology

Jefferson, P. (2012) And Now the Shipping Forecast

Maloney. A. (2017) And Now, The Weather…: A Celebration of our National Obsession

Nobbs, P. (2016) The Story of the British and Their Weather

Revkin, A. and Mechaley, L. (2018) Weather: An Illustrated History

 

This article was featured in the November 2018 issue of Radio User